Error message in Sonar X2

I've been getting the following VST.NET error when I load up any VST.NET vsti (tried my own project as well as a sample VST.NET plugin) in Sonar X2:

The error message also sometimes occurs when hitting play or stop. I've tried this in 32-bit Sonar X2 and 64-bit sonar X2 on windows 7 and windows 8 and got the error message in all cases. Any idea what could be causing it? Looks like there is a signed/unsigned
mismatch somewhere.

The comments in the vst interface file says: "-64 to +63 cents; for scales other than 'well-tempered'"
That is where I got the validation values from. At second glance you could also interpret this comment as "anything goes".
Typical in VST :-P